What Is the Difference Between a Possum and an Opossum?

While both possums and opossums are marsupials, they are, technically and scientifically, two very different animals. The opossum is a mammal belonging to the family of marsupials located in North America. Possums, on the other hand, are marsupials of Australian origin. The possums were given that name because of the close semblance to the opossums of North America. The possums are sometimes called common brushtail possums. The confusion between the two arose after Sir Joseph Banks decided to name the Australian creature as a possum. The reason for the naming was because he thought that the two looked similar.

Differences Between Possums and Opossums

Different Orders 

The first and the most obvious difference between the two marsupials is that they belong to different orders. While they are both members of the marsupial family, their orders are the Didelphimorphia and Diprotodontia for the opossum and possum respectively.

Physical Appearance 

A North American opossum. 

An Australian possum. 

• The color of opossums is generally between pure white and black.
• Their bodies are generally grayish-white while both feet and ears are black. 
• Their fur is very coarse.
• Opossums are relatively smaller than possums with their lengths averaging between 3 and 22 inches while their weight ranges between 1 and 10 pounds.
• The largest of opossums are about the size of an average domestic cat.
• Opossums have large canines and small incisors.
• Besides the stretched snouts, they have a plantigrade posture, meaning they can walk as humans do with their heels touching the ground. Their tails, which are bare like those of rats, are capable of grabbing small objects for short periods.
• By comparison, possums are considered less threatening looking. The length of possums ranges from the length of a human finger to four feet, while their weight ranges from six ounces to 32 pounds. The biggest possums rarely grow beyond the size of a house cat. Their colors are more diverse including black, chinchilla gray, and fox silver-gray and gold than those of opossums. Their tails are bushy unlike those of the opossum. Further, they have musk gland located behind the ears that are responsible for producing a rank scent.

Geographic Location

There is another difference between the two regarding geographical location. Although they inhabit North America, opossums originated from South America then moved north. Opossums are also located in parts of Southern Canada, Chile, and Argentina.

On the other hand, possums are native to Australia, Sulawesi (Indonesia), and New Guinea. Some of these animals were also taken to New Zealand. The number of species of the possums is 64 while there are more than 60 opossum species.

Playing Possum

An interesting behavior by the American opossum led to the birth of the phrase “playing possum.” This phrase arose because of the common defensive mechanism to pretend to be dead or asleep if under attack or threat from predators. While in this involuntary defensive state, their mouths will be open, lips turn black, teeth show, secrete a foul liquid, and foam appears from the mouth.